Nineteen American citizens have reported symptoms similar to those suffered by U.S. diplomats who had been identified as victims of alleged attacks in Cuba.

“Since September 29, the Department of State has been contacted by 19 U.S. citizens who reported experiencing symptoms similar to those listed in the Travel Warning after visiting Cuba,” a spokesperson for the State Department’s Bureau of Western Hemisphere Affairs told the Miami Herald in an email.

“We continue to urge U.S. citizens to reconsider travel to Cuba,” she added.

In late September, the State Department issued a travel warning advising Americans not to travel to Cuba because they could become victims of mysterious attacks such as those suffered by 24 diplomats and their families while they were stationed in Havana. The U.S. also removed most of the staff at its embassy in the Cuban capital.